Hacks are currently undetected.
seeing as you are both subscribers you can check the WarZ section out, in there are stickies that Tom has posted. He updates them everytime there is a new feature and will update them if they are detected.
Some things to take notice of. If a new patch is released for WarZ, do not try and hack untill Tom has gave the all clear, this is how bans are issued.
But to anwser your questions, the hack is UNDETECTED and YES you would be notified if they were detected.
GV